Effect of Hydro-Oleophobicity Coating on Swelling and Insulation Properties of SiR for Cable Accessories

The swelling effect and deterioration of high-voltage cable accessories can easily lead to insulation breakdown and seriously threaten the safe and stable operation of high-voltage cables. This article proposes the preparation of a surface hydro-oleophobicity coating to enhance the swelling resistance of the cable accessories. Wet thermal aging experiments were conducted on silicone rubber (SiR), with subsequent analysis of the interface properties, swelling properties, and electrical properties. The results showed that the SiO2 nanoparticle coating containing carbon-fluorine bonds was formed on the surface of the modified SiR, which enhanced the barrier effect of the sample surface on moisture and silicone grease and suppressed the swelling and damage effect on the SiR. The modification restrained the damage of aging to the surface structure of SiR and improved the surface conductivity, flashover voltage, and potential decay rate.